Improvement in sink gas-traps



J. A. THOMPSON.

Sink-Gas Trap.

Patented Dec. 11, 1877.

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INVENTOH N.FETERS, PHOTO-LITROGRAPHER. WASHINGTON, D, (L

UNITED STATES PATENT OEEIOE.

JOHN inTHoMrsoN, or CHICAGO, ILLINOIS.

IM PROVEMENT IVN SINK GAS-TRAPS.

Specification forming part of Letters Patent No. 197,952, dated December 11, 1877; application filed October 20, 1877.

To all whom it may concern:

Be it known that I, JOHN A. THOMPSON, of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Sink Gas-Traps, of which the follo wing is a specification, reference being had to the accompanying drawing, in which- Figure 1 is a central cross-section of my improved trap; Fig. 2, an elevation thereof; Fig. 3, a vertical central section of the same combined with an outer case or vessel, and Fig. 4 a like representation of a modification thereof.

In the drawing, A represents the bottom of a sink or basin, and B is an orifice therein, to allow the contents of the sink to flow away to the drain or sewer. G is an ordinary perforatedplate covering the orifice B,'to prevent large solid parts from entering and choking the drain-pipe. D is a comparatively heavy metal disk, made preferably of cast-iron. E is a lifting knob or handle, projecting vertically from the central part of the upper face of the disk D. F is an annular bead or rib, projecting horizontally from the lower edge of the disk. G is an annular packing, consisting preferably of rubber, and applied to the disk by being stretched over the bead or rib F, the packing being wide enough, when so applied, to lap the under face of the disk a considera ble way inwardly from its perimeter or edge, as shown at a.

I deem it best to arch or raise the central part of the lower face of the disk D above the part in contact with the packing or Washer G, so as to avoid unnecessary care in making the under face of the disk smooth and even. Af-

ter making the disk in this manner, and providing it with a packing, G, in the manner described, the sewer-gas will be efiectually prevented (by placing the disk over the orifice B in the manner shown in Figs-1 and 3) from escaping into the room through the said orifice.

H is an outer case or vessel, applied to the disk D in the manner represented in Fig. 3,

the disk then serving as the bottom of the vesble diaphragm or bottom, I, impervious to gas,

and consisting, preferably, of rubber. The bottom I may be held or pressed closely upon the plate G, for the purpose set forth, by placing some sand or like material in the vessel, as represented at J. V

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is- A sink gas-trap consisting of the disk D, provided with the bead F and packing G, the said bead and packing arranged, substantially as described, with relation to each other and the disk.

JOHN A. THOMPSON. Witnesses F.- F. WARNER, JAMES LEDDY. 

